Acetylene Black Paste Electrode Research Articles

Sensitive and rapid detection of methotrexate in serum and saliva with MWCNT and STAC modified acetylene black paste electrode

Sensitive and rapid detection of methotrexate in serum and saliva with MWCNT and STAC modified acetylene black paste electrode

Salicylaldehyde functionalized chitosan for electrochemical sensitive sensor: Simultaneous determination of catechol and hydroquinone

Salicylaldehyde functionalized chitosan (S-CHIT) was prepared and electrochemical sensor based on the above material and acetylene black paste electrode (ABPE) were constructed. A new method for the simultaneous detection of catechol (CC) and hydroquinone (HQ) was established. The results of Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) showed that S-CHIT had been successfully synthesized and attached to the surface of ABPE. Cyclic voltammetry (CV) and second-order derivative linear sweep voltammetry (SDLSV) were used to investigate the electrochemical behaviors of CC and HQ on the S-CHIT/ABPE. In 0.1 M H2SO4 solution, CC and HQ produced a pair of reversible redox peaks with good shape on the modified electrode. The quantitative determination of CC and HQ was performed by SDLSV using the oxidation signal. The difference of the oxidation peak potentials between CC and HQ was 112 mV. In the presence of 50 µM of the respective isomer, the linear concentration range of CC and HQ is 0.6 μM to 80 μM and 1.0 μM to 80 μM respectively, and the corresponding detection limits are 0.1 μM and 0.4 μM. The method was applied to the simultaneous determination of CC and HQ in water samples. The results show that S-CHIT/ABPE is a promising electrochemical sensor for the simultaneous detection of CC and HQ.

Application of a Simple and Sensitive Electrochemical Sensor in Simultaneous Determination of Paracetamol and Ascorbic Acid

A new electrochemical sensor for the quick determination of both paracetamol (ACOP) and ascorbic acid (AA) was prepared using an acetylene black paste electrode modified with polyvinylpyrrolidone and graphene composite (PVP-GR/ABPE). Second derivative linear sweep voltammetry (SDLSV) and cyclic voltammetry (CV) were then used to investigate the electrochemical behavior of both ACOP and AA on this PVP-GR/ABPE. The results demonstrate that the two analytes have good resolution and strong electrochemical signal responses. Due to the interconnected effects of PVP, GR, and AB ternary composite, the designed electrode has several beneficial characteristicsincluding good adsorption ability, significant specific surface area, and good conductivity. The voltammetric responses of ACOP and AA on the PVP-GR/ABPE show that the modified electrode displayed good electrocatalytic properties for the chemical reactions of both ACOP and AA, with the linear range of 0.01–100 μM for ACOP and the linear range of 6–1000 μM for AA. The detection limits of 6.0 nM (ACOP) and 1.0 μM (AA) were obtained, respectively. The sensor has successfully been used in the measurement of ACOP and AA in real samples, indicating that this method is potentially applicable for routine biomedical and chemical sensing in vitro diagnostically.

Fast and ultrasensitive trace malachite green detection in aquaculture and fisheries by using hexadecylpyridinium bromide modified electrochemical sensor

An ultrasensitive voltammetric method for fast determination of trace malachite green in aquaculture and fisheries using an acetylene black paste electrode modified with hexadecylpyridinium bromide was established. Compared with the unsatisfactory response at carbon paste electrode, the performance of the modified electrode for the electrooxidation of malachite green was improved significantly. The parameters for quick and sensitive detection of malachite green were optimized, including the type of supporting electrolyte, solution pH, accumulation potential and accumulation time. By using the technique of second derivative linear sweep voltammetry, the peak current was linearly related to malachite green concentration in the wide range of 0.02 μM ∼ 40 μM. After a 150 s preconcentration, a low method detection limit of 4.0 nM was obtained (Signal to noise ratio of 3). In addition, the hexadecylpyridinium bromide modified acetylene black paste electrode exhibited excellent intra-day repeatability (RSD = 2.7 %) and inter-day repeatability (RSD = 3.8 %), good stability and anti-interference ability. Finally, the method was applied to the determination of malachite green in water and fish samples with satisfied relative recoveries of 96.0∼104.0 %, suggesting that this method has good accuracy.

New voltammetric method for determination of tyrosine in foodstuffs using an oxygen-functionalized multi-walled carbon nanotubes modified acetylene black paste electrode

In this paper, acetylene black paste electrode (ABPE) was prepared and modified by oxygen-functionalized multi-walled carbon nanotubes (MWCNT-COOH). The fabricated MWCNT-COOH/ABPE was further used for the investigation on the electrochemical behavior of tyrosine by cyclic voltammetry and second-order derivative linear sweep voltammetry. In 0.1 M pH 2.6 phosphate buffer solution, a well-defined anodic peak appeared at 924 mV, which was attributed to the electrooxidation of tyrosine on the modified electrode. The electrochemical parameters of tyrosine on the modified electrode were calculated. Under the optimal conditions, the oxidation peak current of tyrosine varies linearly with its concentration in the range of 0.04−1.0 μ M, 1.0−60 μ M and 60−600 μ M, and the detection limit is 0.02 μM. The MWCNT-COOH/ABPE was applied to the determination of tyrosine in food with satisfactory results.

Electrochemical detection of methotrexate in serum sample based on the modified acetylene black sensor

A novel acetylene black (AB) sensor modified with stearyltrimethylammoniumbromide (STAB) was fabricated and applied to the determination of methotrexate (MTX) in serum. For the strong adsorption of STAB and the high catalytic capacity of AB, the prepared sensor performed better adsorption and electrochemical catalysis capacity compared with acetylene black paste electrode (ABPE). Several factors affecting the performance of the sensor, such as the construction of the sensor and the parameters affect the electrochemical catalysis were optimized carefully on sequences in this study. The prepared sensor showed favorable performance in the determination of MTX with the linear range of 0.005 μM to 7.0 μM and the detection limit of 3.07 nM. Furthermore, the fabricated sensor exhibited good stability and repeatability, which was of importance in the electrochemical detection. Finally, the established electrode was employed in the detection of MTX in real sample of serum, which demonstrated the reliable and accurate of the prepared method. It is obvious that the prepared sensor existed great potential in the determination of MTX, which could provide a new approach for the fast and low-coat detection for MTX.

A Simple and Efficient Molecularly Imprinted Electrochemical Sensor for the Selective Determination of Tryptophan

In this paper, a tryptophan (Trp) molecularly imprinted chitosan film was prepared on the surface of an acetylene black paste electrode using chitosan as the functional polymer, Trp as the template molecule and sulfuric acid as the crosslinking agent. The surface morphologies of non-imprinted and imprinted electrodes were characterized by scanning electron microscopy (SEM). The formation of hydrogen bonds between the functional polymer and the template molecule was confirmed by infrared spectroscopy. Some factors affecting the performance of the imprinted electrode such as the concentration of chitosan, the mass ratio of chitosan to Trp, the dropping amount of the chitosan-Trp mixture, the solution pH, and the accumulation potential and time were discussed. The experimental results show that the imprinted electrode exhibit good affinity and selectivity for Trp. The dynamic linear ranges of 0.01–4 μM, 4–20 μM and 20–100 μM were obtained by second derivative linear sweep voltammetry, and the detection limit was calculated to be 8.0 nM. The use of the imprinted electrode provides an effective method for eliminating the interference of potentially interfering substances. In addition, the sensor has high sensitivity, reproducibility and stability, and can be used for the determination of Trp in pharmaceutical preparations and human serum samples.

Facile and Ultrasensitive Determination of 4-Nitrophenol Based on Acetylene Black Paste and Graphene Hybrid Electrode.

4-nitrophenol (4-NP) is a hazardous waste and a priority toxic pollutant identified by US Environmental Protection Agency (EPA). Hence, in this paper, a voltammetric sensor was proposed for the direct and sensitive detection of 4-nitrophenol (4-NP) at nanomolar level in complex matrices by using graphene and acetylene black paste hybridized electrode (GR/ABPE). Under optimal conditions, the calibration curve demonstrates a linear relationship for 4-NP in the range from 20 nM to 8.0 μM and 8.0 μM to 0.1 mM separately with the detection limit of 8.0 nM. In addition to it, the performance of the GR/ABPE in practical applications was evaluated by detecting 4-NP in various water samples, and satisfactory recoveries were realized. Therefore, GR/ABPE may have a great potential application for facile and sensitive detection of 4-NP in complex matrices at nanomolar level.

A novel sensor based on nanobiocomposite Au-­In2O3-­chitosan modified acetylene black paste electrode for sensitive detection of antimycotic ciclopirox olamine

For the first time, a sensitive conductive nanobiocomposite sensor consisting of Au–In2O3 nanocomposite and chitosan (CS) was successfully prepared and used for the modification of acetylene black paste electrode (Au-­In2O3­-CS/ABPE). The phase structures, composition and morphology of Au–In2O3 nanocomposite were characterized by X-ray diffraction (XRD), energy–dispersed X-ray (EDX) and transmission electron microscopy (TEM). Electrochemical activities and surface analysis of the biosensor electrode Au­-In2O3­-CS/ABPE were investigated using scanning electron microscopy (SEM), cyclic voltammetry and square wave voltammetry. The modified electrode showed an excellent electrochemical activity toward the electro–oxidation of the antimycotic ciclopirox olamine (CPX) leading to a significant improvement in sensitivity as compared to the bare ABPE. The proposed biosensor demonstrated linearity in the range 0.199 – 16.22µmolL−1, with high sensitivity (64.57μAµmolL−1cm−2) and detection limit of 6.64 × 10−9molL−1 CPX. The analytical performance of this biosensor was evaluated for detection of CPX in pharmaceutical formulations with good accuracy and precision. This proposed method was validated by UPLC and the results are in agreement at the 95% confidence level.

Acetylene black paste electrode modified with molecularly imprinted polymers/graphene for the determination of bisphenol A.

A novel nanocomposite of molecularly imprinted polymers and graphene sheets was fabricated and used to obtain a highly conductive acetylene black paste electrode with high conductivity for the detection of bisphenol A. The two-dimensional structure and the chemical functionality of graphene provide an excellent surface for the enhancement of the sensitivity of the electrochemical sensor and the specificity of molecularly imprinted polymers to improve detection of bisphenol A. The synergistic effect between graphene and molecularly imprinted polymers confers the nanocomposite with superior conductivity, broadened effective surface area and outstanding electrochemical performance. Factors affecting the performance of the imprinted sensor such as molecularly imprinted polymers concentration, foster time and scan rate are discussed. The sensor successfully detects bisphenol A with a wide linear range of 3.21 × 10-10 to 2.8 × 10-1 g/L (R = 0.995) and a detection limit of 9.63 × 10-11 g/L. The fabricated sensor also possessed high selectivity and stability and exhibits potential for environmental detection of contaminants and food safety inspection.

Zwitterionic Surfactant Modified Acetylene Black Paste Electrode for Highly Facile and Sensitive Determination of Tetrabromobisphenol A.

A electrochemical sensor for the highly sensitive detection of tetrabromobisphenol A (TBBPA) was fabricated based on acetylene black paste electrode (ABPE) modified with 3-(N,N-Dimethylpalmitylammonio) propanesulfonate (SB3-16) in this study. The peak current of TBBPA was significantly enhanced at SB3-16/ABPE compared with unmodified electrodes. To further improve the electrochemical performance of the modified electrode, corresponding experimental parameters such as the length of hydrophobic chains of zwitterionic surfactant, the concentration of SB3-16, pH value, and accumulation time were examined. The peak currents of TBBPA were found to be linearly correlated with its concentrations in the range of 1 nM to 1 µM, with a detection limit of 0.4 nM. Besides, a possible mechanism was also discussed, and the hydrophobic interaction between TBBPA and the surfactants was suggested to take a leading role in enhancing the responses. Finally, this sensor was successfully employed to detect TBBPA in water samples.

Electrochemical behavior and voltammetric determination of vanillin based on an acetylene black paste electrode modified with graphene–polyvinylpyrrolidone composite film

The graphene–polyvinylpyrrolidone composite film modified acetylene black paste electrode (GR–PVP/ABPE) was fabricated and used to determine vanillin. In 0.1M H3PO4 solution, the oxidation peak current of vanillin increased significantly at GR–PVP/ABPE compared with bare ABPE, PVP/ABPE and GR/ABPE. The oxidation mechanism was discussed. The experimental conditions that exert influence on the voltammetric determination of vanillin, such as supporting electrolytes, pH values, accumulation potential and accumulation time, were optimized. Besides, the interference, repeatability, reproducibility and stability measurements were also evaluated. Under the optimal experimental conditions, the oxidation peak current was proportional to vanillin concentration in the range of 0.02–2.0μM, 2.0–40μM and 40–100μM. The detection limit was 10nM. This sensor was used successfully for vanillin determination in various food samples.

Simultaneous voltammetric determination of 2-nitrophenol and 4-nitrophenol based on an acetylene black paste electrode modified with a graphene-chitosan composite

We describe a simple and sensitive voltammetric method for the simultaneous determination of 2-nitrophenol and 4-nitrophenol. It is based on the use of an acetylene black paste electrode modified with a graphene-chitosan composite film (denoted as Gr-Chit/ABPE). The reduction peak currents of 2-nitrophenol (at −252 mV) and of 4-nitrophenol (at −340 mV) in pH 1.0 solution increase significantly at the Gr-Chit/ABPE in comparison to a bare ABPE. Factors affecting sensitivity were optimized and a linear relationship is found between peak current and the concentrations of 2-nitrophenol (in the 0.4 μM to 80 μM range) and for 4-nitrophenol (in the 0.1 μM to 80 μM range). The detection limits (at an SNR of 3 and after a 30-s accumulation time) are 200 nM for 2-nitrophenol and 80 nM for 4-nitrophenol, respectively. The modified electrode was successfully applied to the direct and parallel determination of 2-nitrophenol and 4-nitrophenol in spiked water samples.

Electrochemical determination of bisphenol A in plastic bottled drinking water and canned beverages using a molecularly imprinted chitosan–graphene composite film modified electrode

Herein, a novel electrochemical sensor based on an acetylene black paste electrode modified with molecularly imprinted chitosan–graphene composite film for sensitive and selective detection of bisphenol A (BPA) has been developed. Several important parameters controlling the performance of the sensor were investigated and optimised. The imprinted sensor offers a fast response and sensitive BPA quantification. Under the optimal conditions, a linear range from 8.0nM to 1.0μM and 1.0 to 20μM for the detection of BPA was observed with the detection limit of 6.0nM (S/N=3). Meanwhile, the fabricated sensor showed excellent specific recognition to template molecule among the structural similarities and coexistence substances. Furthermore, this imprinted electrochemical sensor was successfully employed to detect BPA in plastic bottled drinking water and canned beverages.

Acetylene black paste electrode modified with graphene as the voltammetric sensor for selective determination of tryptophan in the presence of high concentrations of tyrosine

A reliable sensor was fabricated by modifying an acetylene black paste electrode with graphene (denoted as GR/ABPE) for sensitive and selective determination of tryptophan (Trp). Due to the high sorption ability, large surface area and numerous active sites, the GR/ABPE showed a strong enhancement effect on the oxidation of Trp, and greatly increased the peak current. The parameters affecting the Trp determination were investigated. In 1.0M H2SO4 the voltammetric responses of Trp and tyrosine (Tyr) were well separated into two distinct peaks with peak potential difference (ΔEpa) of 115mV. Under the optimized conditions, in the presence of 0.1mM Tyr, the oxidation peak current of Trp was proportional to its concentration in the range between 0.1μM and 0.1mM, with the limit of detection of 60nM (S/N=3). The GR/ABPE was applied to the direct detection of Trp in pharmaceutical and biological samples with satisfactory results. This work provides a simple and easy approach to selective detection of Trp in the presence of Tyr.

Electrochemically reduced graphene oxide modified acetylene black paste electrode for the sensitive determination of bisphenol A

This paper has presented a novel strategy to carry out direct and sensitive determination of bisphenol A (BPA) based on the graphene modified acetylene black paste electrode (GR/ABPE). This modified electrode was obtained by one-step potentiostatic reduction of exfoliated graphene oxide sheets on the surface of ABPE. Due to the unique structure and extraordinary properties of GR and AB, the fabricated sensor displayed greatly improved voltammetric response to BPA compared with the conventional carbon paste electrode. Under the optimized conditions, the linear range for the detection of BPA was from 0.8nM to 10.0nM, 10.0nM to 8.0μM and 8.0μM to 0.1mM, with a detection limit (S/N=3) of 0.6nM. Additionally, this newly-developed method possesses some obvious advantages including extreme simplicity, rapid response and low cost. The practical analytical performance of the GR/ABPE was examined by evaluating the detection of BPA in plastic products with satisfied recovery.

Sensitive determination of bisphenol A in plastic products by derivative voltammetry using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan

A sensitive and reliable electrochemical method was developed for determination of bisphenol A (BPA) in plastic products using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan (denoted as S-CHIT/ABPE). In the second-order derivative linear sweep voltammetry technique, BPA yielded a very sensitive and well-defined oxidation peak at 842 mV in 0.2 mol L−1 HCl solution. Owing to its unique structure and extraordinary properties, S-CHIT/ABPE showed higher accumulation efficiency toward BPA compared with bare ABPE, and significantly enhanced the oxidation peak current of BPA. Under the optimum conditions, the oxidation peak current was proportional to the concentration of BPA over the range of 4.0 × 10−8 mol L−1 ∼ 1.0 × 10−5 mol L−1. The detection limit (S/N = 3) was 2.0 × 10−8 mol L−1. The fabricated S-CHIT/ABPE not only exhibited strong adsorption capacity toward BPA, but also provided remarkable stable and quantitatively reproducible analytical performance. Additionally, this newly-developed method possesses some obvious advantages including high sensitivity, extreme simplicity, rapid response and low cost.

Acetylene black paste electrode modified with a molecularly imprinted chitosan film for the detection of bisphenol A

We report on a voltammetric sensor for bisphenol A (BPA) that is based on an acetylene-black paste electrode modified with a chitosan film molecularly imprinted for BPA. The sensor responds linearly to BPA in the 80 nM to 10 μM concentration range, and the detection limit is 60 nM (at an S/N of 3). The use of a molecular imprint provides an efficient way for eliminating interferences from potentially interfering substances. The high sensitivity, selectivity and stability of the sensor demonstrate its practical application for the determination of BPA in plastic samples.

Simultaneous determination of ascorbic acid and rutin in pharmaceutical preparations with electrochemical method based on multi-walled carbon nanotubes–chitosan composite film modified electrode

In this paper, the simultaneous voltammetric determination of ascorbic acid (AA) and rutin (Ru) has been achieved at an acetylene black paste electrode modified with multi-walled carbon nanotubes–chitosan composite film (denoted as MWCNTs–CHIT/ABPE). Compared with bare electrode, the peak currents of AA and Ru at MWCNTs–CHIT/ABPE increased greatly and the anodic peak potential difference (ΔEpa) between AA and Ru are up to 342mV, which is undoubtedly attributed to the unique characteristics of AB and MWCNTs such as excellent electric conductivity, high surface area and strong adsorptive abilities, resulting in higher accumulation efficiency to AA and Ru. The influences of some experimental conditions on the oxidation of AA and Ru were tested and the calibration plot was examined. Under the optimized condition, a good linearity was obtained in the concentration range of 1μM–0.4mM for AA in the presence of 10μM Ru and 20nM–10μM for Ru in the presence of 1mM AA. The detection limits (S/N=3) of AA and Ru are 0.8μM and 10nM, respectively. The proposed method was successfully applied to the simultaneous determination of AA and Ru in pharmaceutical samples with reliable recovery.

Highly sensitive and simultaneous determination of ascorbic acid and rutin at an acetylene black paste electrode coated with cetyltrimethyl ammonium bromide film

A simple and highly sensitive electrochemical method for the simultaneous and quantitative detection of ascorbic acid (AA) and rutin was developed, based on an acetylene black paste electrode coated with cetyltrimethyl ammonium bromide film (denoted as CTAB/ABPE). In 0.1molL−1 HCl aqueous solution, the prepared modified electrode showed higher accumulation efficiency toward AA and rutin compared with bare ABPE, and significantly enhanced the peak currents of AA and rutin. The difference of the anodic peak potentials between AA and rutin was about 350mV, which is large enough to determine AA and rutin individually and simultaneously. The electrochemical behaviors of AA and rutin were carefully investigated with the electrochemical parameters calculated. Under optimized conditions, the linear calibration ranges were 2.0×10−6M to 1.0×10−3M for AA and 6.0×10−9M to 1.0×10−5M for rutin, and the detection limits (S/N=3) were 1.0×10−6M and 4.0×10−9M, respectively. This modified electrode was applied to direct simultaneous determination of AA and rutin in the selected pharmaceutical samples without previous chemical or physical separations. Moreover, the CTAB/ABPE offers some advantages including low cost, facility of construction, good reproducibility and high stability.